Abstract: This paper numerically studies the influence of air supply changes on the dynamics of the flow field in a tangential furnace using the finite element method. A combination of structured and unstructured grids can reduce false diffusion. Experiments on a pilot-scale furnace essentially verify the reliability of the numerical scheme. Numerical studies show that different typical changes in the air supply at one or adjacent two burners would always skew the tangential flow field in the furnace correspondingly. Furthermore, the fault of the tangential flow field caused by abnormal inflow at local burners dynamically follows the primary solenoidal flow stream to rotate upward. Within the burner region, the impact of the fault flow weakens, but afterward, free of restraint from inflows, the skewness of the tangential center increases. Therefore, the dependence characteristics of the flow field in furnace on the inflow air conditions are recovered, providing reference to study, control and adjustment of the aerodynamic field in furnace.